library(tidyverse)
dta_post = read_csv("post_data.csv") %>%
				mutate(
					type="post"
					)
dta_arrest = read_csv("arrest_data.csv",
                      col_types = "?c?????") %>%
				mutate(
					type="arrest"
					)
dta_single = bind_rows(dta_post, dta_arrest)
save(dta_single, file="dta_single.rdata")